1. Field of the Invention
This invention relates to the field of electronics packaging, and in particular, to high-density electronic modules for housing and interconnecting electronic components located on stacked substrate layers.
2. Description of the Related Art
Increasing the volume density of electronic packaging is crucial for reducing device sizes for a given functionality. Efforts to provide high-density electronic packaging have included three-dimensional stacking technology in an attempt to avoid the inherent geometric constraints of standard two-dimensional semiconductor integrated circuits (xe2x80x9cICsxe2x80x9d). By stacking electronic modules on top of one another and providing interconnections between the modules, the multiple layers can provide additional circuit elements without extending the two-dimensional footprint beyond that of a single module. Certain embodiments have also included heat-conducting, electrically insulating layers to improve heat dissipation during operation of these stacked electronic modules.
Numerous packaging schemes have been developed for stacking silicon-based ICs to increase the volume densities of electronic devices. However, while the silicon wafers of the silicon-based ICs provide rigidity and stability for the electronic elements, the ultimate volume densities of the multilayer stacks are inherently limited due to the thicknesses of the silicon wafers. Lapping off excess silicon from the back side of silicon wafers before stacking has been used to decrease the thickness of the silicon layers, and hence increase the number of layers per unit height. However, this procedure is time-consuming and requires precise machining to avoid damaging the circuit elements.
In accordance with one aspect of an embodiment of the invention, a stack of multilayer modules has a segmentation layer disposed between neighboring multilayer modules. The segmentation layer facilitates the separation of neighboring multilayer modules. The stack of multilayer modules comprises a first multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The stack of multilayer modules further comprises a second multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second multilayer module is disposed to be neighboring the first multilayer module. The stack of multilayer modules further comprises at least one segmentation layer between the first and second multilayer modules. The segmentation layer comprises a metal layer and at least one thermoplastic adhesive layer. When heat is applied, the metal layer conducts heat to the thermoplastic adhesive layer.
In accordance with another aspect of an embodiment of the invention, a method releasably adheres together neighboring multilayer modules of a stack of multilayer modules. The method comprises providing a first multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises providing a second multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second multilayer module is disposed to be neighboring the first multilayer module. The method further comprises disposing a segmentation layer between the first multilayer module and second multilayer module. The segmentation layer comprises a metal layer and a thermoplastic adhesive layer. When heat is applied, the metal layer conducts heat to the thermoplastic adhesive layer.
In accordance with another aspect of an embodiment of the invention, each multilayer module of a stack of multilayer modules has a plurality of layers wherein each layer has a substrate therein. The stack of multilayer modules comprises a first multilayer module comprising a first layer having a top side and bottom side. The first layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The stack of multilayer modules further comprises a second multilayer module comprising a second layer having a top side and bottom side. The second layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The stack of multilayer modules further comprises a metal layer disposed between and adhered to the top side of the first layer and the bottom side of the second layer. The first multilayer module is releasably adhered to the second multilayer module.
In accordance with another aspect of an embodiment of the invention, a method provides a stack of multilayer modules. Each multilayer module has a plurality of layers wherein each layer has a substrate therein. The method comprises providing a first multilayer module comprising a first layer having a top side and bottom side. The first layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises providing a second multilayer module comprising a second layer having a top side and bottom side. The second layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises adhering a metal layer to the top side of the first layer and the bottom side of the second layer. The method further comprises releasably adhering the first multilayer module to the second multilayer module with the metal layer disposed between the first multilayer module and the second multilayer module.
In accordance with another aspect of an embodiment of the invention, each multilayer module of a stack of multilayer modules has a plurality of layers wherein each layer has a substrate therein. The plurality of multilayer modules comprises a first multilayer module comprising a first layer having a top side and bottom side. The first layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The plurality of multilayer modules further comprises a second multilayer module comprising a second layer having a top side and bottom side. The second layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The plurality of multilayer modules further comprises a thermoplastic adhesive disposed between the top side of the first layer and the bottom side of the second layer. The first multilayer module is releasably adhered to the second multilayer module.
In accordance with another aspect of an embodiment of the invention, a method provides a stack of multilayer modules. Each multilayer module has a plurality of layers wherein each layer has a substrate therein. The method comprises providing a first multilayer module comprising a first layer having a top side and bottom side. The first layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises providing a second multilayer module comprising a second layer having a top side and bottom side. The second layer comprises a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises releasably adhering the first multilayer module to the second multilayer module by disposing a thermoplastic adhesive between the top side of the first layer and the bottom side of the second layer.
In accordance with another aspect of an embodiment of the invention, a stack of multilayer modules has a segmentation layer disposed between neighboring multilayer modules. The segmentation layer facilitates the separation of neighboring multilayer modules. The stack of multilayer modules comprises a first multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The stack of multilayer modules further comprises a second multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second multilayer module is disposed to be neighboring the first multilayer module. The stack of multilayer modules further comprises at least one segmentation layer between the first and second multilayer modules. The segmentation layer comprises a plurality of metal layers and at least one thermoplastic adhesive layer. When heat is applied, the metal layers conducts heat to the thermoplastic adhesive layer.
In accordance with another aspect of an embodiment of the invention, a method provides a stack of multilayer modules with a segmentation layer disposed between neighboring multilayer modules. The method comprises providing a first multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises providing a second multilayer module comprising a plurality of active layers each comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second multilayer module is disposed to be neighboring the first multilayer module. The method further comprises releasably adhering the first multilayer module and the second multilayer module by disposing at least one segmentation layer between the first and second multilayer modules. The segmentation layer comprises a plurality of metal layers and at least one thermoplastic adhesive layer. When heat is applied, the metal layers conducts heat to the thermoplastic adhesive layer.
In accordance with another aspect of an embodiment of the invention, a stack of multilayer modules has a segmentation layer disposed between neighboring multilayer modules. The segmentation layer facilitates the separation of neighboring multilayer modules. The stack of multilayer modules comprises a first multilayer module comprising a first active layer comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The stack of multilayer modules further comprises a second multilayer module comprising a second active layer comprising a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second active layer is disposed to be neighboring the first active layer. The stack of multilayer modules further comprises at least one segmentation layer between the first and second active layers. The segmentation layer comprises a metal layer and at least one thermoplastic adhesive layer. When heat is applied, the metal layer conducts heat to the thermoplastic adhesive layer.
In accordance with another aspect of an embodiment of the invention, a method separates a stack of releasably adhered multilayer modules. The method comprises providing a first multilayer module releasably adhered to a second multilayer module by disposing a heat-separating layer between the first and second multilayer modules. The first multilayer module comprises a first layer with a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The second multilayer module comprises a second layer with a substrate, at least one electronic element, and a plurality of electrically-conductive traces. The method further comprises applying heat to the heat-separating layer, thereby releasing the first multilayer module from the second multilayer module. The method further comprises separating the first multilayer module from the second multilayer module.
In accordance with another aspect of an embodiment of the invention, a stack of multilayer modules comprises means for stacking the multilayer modules. The stack of multilayer modules further comprises means for releasably adhering neighboring multilayer modules to one another upon heating. The stack of multilayer modules further comprises means for conducting heat to said means for releasably adhering neighboring multilayer modules to one another.
For the purposes of summarizing the invention, certain aspects, advantages and novel features of the invention have been described herein above. It is to be understood, however, that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.